The Fellowes AeraMax 290 Air Purifier uses 4-stage hospital-type filtration to effectively purify air in large rooms 300 - 600 square feet. The AeraSmart Sensor monitors the air quality and automatically adjusts the fan speed to keep your air purified with ultra-quiet operation. A True HEPA filter with AeraSafe antimicrobial treatment safely removes 99. 97% of airborne particles as small as 0. 3 microns. Backed by a 3-year manufacturer limited warranty. ULTRA-QUIET AIR PURIFIER FOR LARGE ROOMS: recommended for rooms 300 - 600 square feet. ALLERGY PROTECTION WITH TRUE HEPA FILTRATION: Captures up to 99. 97% of particles as small as 0. 3 microns, including allergens, such as pollen, dust, pet dander, and smoke. COLD/FLU READY: Keep air even cleaner in peak seasons with Aera+ Mode proven to reduce 99. 97% of influenza A virus in independent laboratory testing. ELIMINATES ODORS: Carbon air filter actively removes odors and captures volatile organic compounds (VOCs) such as cleaning agents. SENSES AND ADJUSTS: AeraSmart sensor monitors the air quality and automatically adjusts the fan speed to keep air purified. PLASMATRUE TECHNOLOGY: optional setting that utilizes ionization to help safely remove airborne pollutants. EXPANDED FILTER LIFESPAN: AeraSafe antimicrobial treatment applied to the True HEPA filter inhibits the growth of odor and stain-causing microorganisms. Filter indicator: light alerts when to change filters. Compatible with Hepa Filter 9287201. Compatible with Carbon Filter 9324201. Safely removes airborne particles in large sized rooms 300-600 sq. ft.